The Linux Danish/International HOWTO

Niels Kristian Bech Jensen nkbj@sslug.dk

v2.6, 9 March 2000

This document describes how to configure Linux and various Linux
applications for Danish locale standards such as keyboard, font, paper-size etc. It is hoped that Linux users from other places in
Western Europe will find this document useful too.

All European users of almost any operating system have two problems:
The first is to tell the computer that you have a non-American keyboard,
and the second is to get the computer to display the special
characters. To make matters worse some applications will also consider you
an exception if you are not an American and require special options or the
setting of environment variables.

Under Linux you change the way your computer interprets the
keyboard with the commands loadkeys and xmodmap. loadkeys
will modify the keyboard for plain Linux while xmodmap makes the
modifications necessary when the handshaking between X11 and Linux is
imperfect.

To display the characters you need to tell your applications that you
use the ISO-8859-1 (a.k.a. Latin-1) international set of glyphs. This is
not always necessary, but a number of key applications need special
attention.

This HOWTO is intended to tell Danish users how to do this. If
you continue to have problems after reading this you can try the
German HOWTO, the Linux Keyboard and Console HOWTO or the ISO 8859-1 National
Character Set FAQ. Many of the hints contained herein are cribbed from
there. See section
Other documents of relevance for
pointers to these documents. You should also send me a mail describing your
problems.

A final problem is that error-messages, menus and documentation of the
applications are mostly in English. There is a GNU project under way to
address this problem. You can see what it is all about by downloading
the file ABOUT-NLS or the package gettext-0.10.tar.gz (or any
later version) from your favourite mirror of the GNU archive. This
project needs volunteers for the translations. Send a mail to
da-request@li.org with the body ``subscribe'' if you want to contribute
to the Danish part of the project. The documentation in the gettext
package describes how to use such translations in your own programs.

You have two tools for configuring your keyboard. Under plain
Linux you have loadkeys and under X11 you have xmodmap.

To try out loadkeys type one of these two commands:

loadkeys /usr/lib/kbd/keytables/dk.map

or

loadkeys /usr/lib/kbd/keytables/dk-latin1.map

The difference between the two keymaps is that dk-latin1.map
enables `dead' keys while dk.map does not. Dead keys are explained
in section
Dead keys and accented characters. The
program loadkeys and the keymaps are part of the package
kbd-0.??.tar.gz which (with differing version numbers ??) is available
with all Linux distributions.

Usually loadkeys is executed at boot-time from one of the scripts
under the directory /etc/rc.d/. Details vary between distributions.

(Note for non-Danish readers: Support for other languages is enabled
in a similar manner. Use es.map for Spanish keyboards etc.)

Versions of XFree86 up to and including v3.1.2 will normally follow the
keymap used by plain Linux, but you can modify keyboard behavior under X11
with xmodmap. Usually the X11 initialization process will run this
command automatically if you have a file called .Xmodmap in your
home directory.

In XFree86 v3.2 and higher you should have the following Keyboard
section in your /etc/XF86Config (or /etc/X11/XF86Config) file
(it should be made automatically by the program XF86Setup if you choose
a Danish keytable):

For versions of XFree86 up to and including v3.1.2 you should edit the file
/etc/XF86Config (or /etc/X11/XF86Config) and make sure the
line

RightAlt ModeShift

appears in the Keyboard section. Usually you can do this by
uncommenting the appropriate line. In XFree86 v3.1.2 you can use
AltGr as an alias for RightAlt.

The AltGr key should work as expected in XFree86 v3.2 and higher if you
choose Danish keyboard support.

Making {, [, ] and } work under Metro-X

You can't input the characters ``{'' (<AltGr><7>),
``['' (<AltGr><8>), ``]''
(<AltGr><9>) and ``}'' (<AltGr><0>)
under the Metro-X server. This bug has been observed under versions 3.1.5
and 3.1.8 of the server.

To correct this bug you have to edit the file
/usr/X11R6/lib/X11/xkb/symbols/dk and change the lines

Dead keys are those that do not type anything until you hit another
key. Tildes and umlauts are like this by default under plain Linux if
you use the dk-latin1.map keymap. This is the default
behaviour for these keys under Microsoft Windows as well.

Invoking dead key functionality

Invoking dead key functionality under X11R6 sessions
First you must make sure you are running XFree86 v3.1.2 or
higher. Download and install everything related to the newest release if
you have a lower version number. Neither compose nor dead keys will work in
X11R6 applications unless these are compiled with support for accented
(8-bit) character input. An example of such an application is
GNU emacs version 19.30 (or higher.)
Some X11 applications still do not support this input method. Eventually
this situation might improve, but until that happens you can either hack your
applications or submit polite bug reports to the program authors. The latter
approach is often the most efficient. See section
Programming tips for X11 for some advice on what needs to be done.
Next you will have to map a key to Multi_key (Compose.) The
Scroll Lock key is most likely already mapped as such if you use
XFree86 v3.1.2 (you can verify this with the program xev,) and it is
easy to map the right Control key by uncommenting the appropriate line
in the Keyboard section of the XFree86 configuration file (often
/etc/XF86Config or /etc/X11/XF86Config.) If you wish to use
some other key, or if you are using XFree86 v3.2 or higher and want to change
the default, you should put something like

keycode 78 = Multi_key

in your ~/.Xmodmap file. The statement in the example defines
Scroll Lock as the Compose key. The default Compose key in
XFree86 v3.2 and higher is <Shift><AltGr>.
XFree86 v3.2 and higher comes without support for the dead keys on the standard
Danish keyboard. To get this support you have to change a few lines in the
xkb_symbols "basic" section of the file
/usr/X11R6/lib/X11/xkb/symbols/dk. The lines

After these changes you can get support for dead keys by removing the line

XkbVariant "nodeadkeys"

from the Keyboard section of your /etc/XF86Config (or
/etc/X11/XF86Config) file.
(Note for non-Danish readers: There are files for many local keyboard maps in
/usr/X11R6/lib/X11/xkb/symbols.)
The available keystroke combinations are listed in
/usr/X11R6/lib/X11/locale/iso8859-1/Compose. There are some
bugs in that file you will want to fix:

$ (the dollar sign)

There is a bug in the Danish keymaps causing the dollar sign to be accessed
with <Shift><4> instead of <AltGr><4>
by default. If this is a problem for you, determine what keymap you load at
boot-time. You can find it by looking around in the directory
/etc/rc.d/ or simply by paying attention to what happens at boot-time.
On my computer the relevant keymap is called
/usr/lib/kbd/keytables/dk-latin1.map. You can fix the problem by
changing the line

keycode 5 = four dollar dollar

in the keymap file to

keycode 5 = four currency dollar

and then (re-)loading the keytable as described in section
Loading a keytable. Currency (dansk: ``soltegn'')
is the default <Shift><4> character on a Danish keyboard.

This should fix the problem for both X11 and plain Linux.

ø (oslash) and Ø (Oslash)

In some older distributions ``ø'' and ``Ø'' appear as cent and
yen. Find the line for keycode 40 in the keymap file and change it from

keycode 40 = cent yen

to

keycode 40 = +oslash +Ooblique

This bug appears to have been fixed in kbd-0.88.tar.gz and newer versions.

The plus signs are necessary to get Caps Lock working properly. ``Oslash''
can be used as an alias for ``Ooblique'' in kbd-0.90.tar.gz and newer
versions.

A new symbol has been added to the Danish character set: The symbol for the
Euro (the new currency of the European Monetary Union.) A new character set
called ISO-8859-15 a.k.a. latin0 (or latin9) has been created to replace
ISO-8859-1 (latin1.) You must use the
EURO package to get support for
latin0. The package includes both fonts and keymaps.

Dead keys should work under GNU emacs provided you use GNU emacs v19.30 or
higher and XFree86 v3.1.2 or higher (it works for me anyway,) so do not start
researching available elisp packages implementing ``electric keys'' or
anything like that. If you want to implement European keyboard conventions
in emacs without upgrading, the best choice is probably the remap
package available from
SunSite DK.
There are also two packages called iso-acc.elc and iso-trans.elc
included with emacs that have similar functionality, but they are not nearly
as powerful.

groff:

Issue the command as

groff -Tlatin1 <your_groff_input_file>

if you want ISO-8859-1 text output.

Remember to change this in /etc/man.config to get latin1 characters
working in man (don't remove the -mandoc switch.)

ispell --- Spell checking in Danish:

First make sure that you install version 3.1.20 instead of version 4.0 of
ispell. The latter is obsolete and multiple brain-damaged. You can
download the sources for ispell at
the GNU archive
and you can get a Danish dictionary from
SSLUG. Follow
the compilation instructions and you should have no trouble (One caveat: When
defining the variables necessary for compilation you must tell ispell that
Linux is a SysV type OS by defining the variable USG.)

When you have installed the Danish dictionary for ispell you can check
the spelling of a Danish language file by executing the command:

ispell -d danish -T latin1 -w "æøåÆØÅ" <your_danish_text_file>

(Note for non-Danish readers: You can find dictionaries for most Western
languages by reading the file Where included with the sources for
ispell.)

joe:

Issue the command as

joe -asis

or put the following in your ~/.joerc file:

-asis

The hyphen character must be in the first column.

kermit:

This is as close as I can get, but not completely satisfying yet. Put the
following in your ~/.kermrc file:

Actually you just have to define one of the environment variables LANG
or LC_CTYPE. The value does not matter. Read the tcsh man
page for more information.

telnet:

Put one line of the following type in your ~/.telnetrc file for
each host you want to log on to using telnet:

<hostname> set outbinary true

Example:

localhost set outbinary true
foo.bar.dk set outbinary true

TeX/LaTeX:

There are several problems with TeX/LaTeX: You want LaTeX to understand
the special characters and you do not want LaTeX to put in English words
like ``Chapter'' at the beginning of every chapter or use English typesetting
conventions.

Under LaTeX2e the header of your input file should look something like this:

The first usepackage statement ensures that LaTeX will interpret
European characters correctly, so you do not have to use escape codes for
European characters. The second one is not strictly necessary, but it is
recommended including it to use the new EC fonts (previously called DC
fonts.) The third usepackage statement defines a range of standards
for typesetting texts in Danish.

All the major Linux distributions now includes the teTeX package. To
set up teTeX you must run the script texconfig. Here you can choose
Danish hyphenation (dansk: ``orddeling''), A4 papersize for dvips and
xdvi etc.

All new Linux distributions include LaTeX2e, but on older systems you might
come across LaTeX 2.09. If that happens you can use

\documentstyle[a4,isolatin]{article}

to include support for ISO-8859-1 characters and European paper sizes. A
better thing to do would be to ask your system administrator to upgrade
to LaTeX2e.

Denmark is placed in the Central European Time zone (CET or MET,) which (in
the winter) is equivalent to Greenwich Mean Time plus 1 (GMT+1.) You set
the time zone on a Linux system by making a symbolic link between
/usr/lib/zoneinfo/localtime and the file in
/usr/lib/zoneinfo/ with a name corresponding to your zone or
country. Danes will want to execute one of the commands

ln -sf /usr/lib/zoneinfo/MET /etc/localtime

or

ln -sf /usr/lib/zoneinfo/Europe/Copenhagen /etc/localtime

This automatically sets Daylight Saving Time (GMT+2) in the summer.

You synchronize the system time with the CMOS clock by issuing the command
clock as root. If your CMOS clock is set to GMT (a.k.a. UTC --- the
standard on proper Unix systems) use

You can translate files between an ISO-8859-1 formatted text file and
e.g. a DOS text file using codepage 850 with the recode package. A
DOS file called foo.txt would be translated into a proper Unix
file with the command

recode cp850:latin1 foo.txt

recode is available as recode-3.4.tar.gz from all mirrors of
the GNU archive.

The locale support has been updated in libc 5.4.x. You can avoid many of
the individual program setups described in section
International character sets in specific applications if the programs
on your system is prepared for locale support. The Debian distribution comes
with this support if you install the wg15-locale package. Systems with
GNU libc 2 (libc 6.x) support locales by default (see remarks about
Red Hat Linux release 5.0 later in this section.)

If you use a system without locale support, you can add such support using the
following method:

Make sure you have the localedef program installed. It should come
with the library.

Get the locale sources. You can get them from DKUUG. You need to get
both
locale
and
charmap
sources.

Put the locale sources in /usr/share/i18n/locales/ and the
charmap sources in /usr/share/i18n/charmaps/.

Execute the localedef program to build the locale data files:

localedef -ci da_DK -f ISO_8859-1:1987 da_DK

(Note for non-Danish readers: You can build locale data files for other locales
in the same way. All locale and charmap sources are at the DKUUG site.)

To enable support for the Danish locale on a system with locale support you
just have to set one of the following environment variables:

LANG=da_DK

or

LC_ALL=da_DK

Try da_DK.ISO_8859-1 if da_DK does not work.

Both environment variables set all the individual locale catgories. You can
also set a single locale category by using the name of the category as an
environment variable. The locale catogories are:

Locale category Application
--------------- -----------
LC_COLLATE Collation of strings (sort order.)
LC_CTYPE Classification and conversion of characters.
LC_MESSAGES Translations of yes and no.
LC_MONETARY Format of monetary values.
LC_NUMERIC Format of non-monetary numeric values.
LC_TIME Date and time formats.
LC_ALL Sets all of the above (overrides all of them.)
LANG Sets all the categories, but can be overridden
by the individual locale categories.

In Red Hat Linux 5.2 you can set the environment variables LANG and/or
LC_ALL in the file /etc/sysconfig/i18n by adding lines such as
this:

LC_ALL=da_DK

A few programs such as bash and GNU emacs still need specific
setup as described in section
International character sets in specific applications, but most
should work without further attention. Programs such as nvi which
did not work with 8 bit characters before should work now.

Locale support should be more common as distributions based on the new
GNU libc 2 become available. Beware that although Red Hat Linux release
5.0 comes with GNU libc 2, the locale support is not working. You have to
build the locale data files by executing localedef yourself. You can build
the Danish locale data files with the following command:

localedef -c -i da_DK -f ISO-8859-1 da_DK

As of glibc-2.0.7-4.i386.rpm the locale data files are included with the
libraries and this is no longer necessary.

Now your program will automagically look up the LC_CTYPE variable
and interpret dead keys etc. according to the Compose tables in
/usr/X11R6/lib/X11/locale/. This should work for all Western European
keyboard layouts and is entirely portable. As XFree86 multilanguage support
gets better your program will also be useful in Eastern Europe and the
Middle East.

This method of input is supported by Xt, Xlib and Motif v1.2 (and
higher.) According to the information I have available it is only partially
supported by Xaw. If you have further information on this subject I would like
to hear from you.

This section was adapted from a more extensive discussion in Michael
Gschwind's Programming for Internationalization. See section
Other documents of relevance for a pointer to that document.

To get Danish texts on menus, buttons, etc. in a well behaved X11 application,
you just have to translate the resource strings defining the texts. Jacob
Nordfalk has done such translations for a lot of applications including
Netscape and Ghostview. The translations and a description of how to
install them can be found at
this site.

Thanks to Peter Dalgaard, Anders Majland, Jon Haugsand, Jacob Nordfalk, the
authors of the German HOWTO, Michael Gschwind and numerous others for
suggestions and help with several questions. And a big thanks to the people
at Aalborg University Center for writing and making available several of the
packages described in this document. A special Thank You to Thomas Petersen;
the original author of this document.

Although the information given in this document is believed to be correct,
the author will accept no liability for the content of this document. Use
the tips and examples given herein at your own risk.